Trim
brisket and rub all over with the garlic. Combine celery seeds, pepper,
ginger and bay leaves, then rub into all sides of the brisket. Mix the
tomato paste, soy, Worcestershire and sugar, and smear this all over
the meat. Score the fat side of the brisket and place the onions on
top, and place the meat in a heavy nonstick high-sided roasting pan.
Cover tightly with aluminum foil. Cook for 4 hours.

Open the foil
to expose the onion-covered top, and cook for another hour. Remove meat
to a heated plate and keep warm. Place the roasting pan on the stovetop
over medium-high heat, and degrease sauce with the bottle of beer until
the sauce has reduced to a pleasant consistency. [Note: Though it's
truly delicious right out of the oven, the flavor improves if cooked a
day ahead; refrigerate in the sauce, and slice cold.] Serve at room
temperature, or reheat.